Are you sure it isn't a fox? Cat bury their excrement.

Only the boss cat of the neighbourhood does this. The others all bury it.

Tom cats do it sometimes, meaning unneutered cats, but other cats will do it if the grass isn't kept short. Most harmless solution is to invest in one of these, there are several versions on the market

https://www.amazon.co.uk/PestBye-Battery-Operated-Activated-Repellent/dp/B004YCUT4W

I have the next door female cat coming in my garden to use as a toilet and she does not bury her mess as it smells
and she does it in shrubs. I have sprayed with Jayes liquid watered down. It seems to do the trick but you do get the faint wiff of Jayes. Better then cats poo smell which is obnoxious.